The earliest sense of anxious (in the 17th century) was “troubled” or “worried”: We are still anxious for the safety of our dear sons in battle. Its meaning “earnestly desirous, eager” arose in the mid-18th century: We are anxious to see our new grandson. Some insist that anxious must always convey a sense of distress or worry and object to its use in the sense of “eager,” but such use is fully standard.